VISIBLE IMAGERY HAS OCCASIONALLY REVEALED AN EYE TRYING TO
FORM...BUT THAT FEATURE HAS NOT BEEN PERSISTENT.

NEVERTHELESS...THE CYCLONE CONTINUES TO INCREASE IN ORGANIZATION...WITH SOLID CONVECTIVE BANDS AND UPPER-LEVEL OUTFLOW THAT IS WELL-DEVELOPED IN ALL QUADRANTS. THE UNDERLYING WATERS OF THE NORTHWESTERN CARIBBEAN SEA ARE QUITE WARM...AND TO SOME DEPTH BENEATH THE SURFACE...SO THERE ARE NO APPARENT IMPEDIMENTS TO ADDITIONAL STRENGTHENING BEFORE GUSTAV REACHES WESTERN CUBA.

EVEN RAPID INTENSIFICATION IS POSSIBLE...AS SUPPORTED BY THE LATEST SHIPS-BASED RAPID INTENSIFICATION INDEX THAT SHOWS A 35 PERCENT CHANCE OF AN INTENSITY INCREASE OF 30 KT OR MORE DURING THE NEXT 24 HOURS.

SO IT IS POSSIBLE THAT GUSTAV COULD REACH MAJOR HURRICANE STATUS PRIOR TO CROSSING WESTERN CUBA. PASSAGE OVER CUBA WILL NOT LIKELY HAVE MUCH IMPACT ON THE STORM'S STRENGTH...AND ALL GUIDANCE FORECASTS A STRENGTHENING TREND OVER THE SOUTHERN GULF...WITH SLIGHT WEAKENING POSSIBLE IN THE NORTHERN GULF.

THE OFFICIAL FORECAST AGAIN CALLS FOR A MAJOR HURRICANE OVER THE GULF...AND DESPITE THE WEAKENING IMPLIED BY THE LESSER INTENSITY OVER LAND AT 96 HOURS...GUSTAV COULD MAKE FINAL LANDFALL ALONG SOME PORTION OF THE NORTHERN GULF COAST AS A MAJOR HURRICANE.

GUSTAV HAS TURNED MORE TO THE RIGHT AND SPED UP A LITTLE...NOW MOVING AT ABOUT 305/10...AS IT HEADS FOR A BREAK IN THE SUBTROPICAL RIDGE OVER THE EASTERN GULF OF MEXICO.

THE PORTION OF THAT RIDGE THAT IS INTACT OVER THE SOUTHERN PLAINS OF THE UNITED STATES IS FORECAST BY ALL MODELS TO EVOLVE INTO A DEEP-LAYER HIGH THAT WILL REACH THE NORTHEASTERN U.S. IN A FEW DAYS.

THERE ARE IMPORTANT DIFFERENCES AMONG THE MODELS...HOWEVER...IN HOW MUCH RIDGING WILL EXTEND SOUTHWESTWARD FROM THAT HIGH TOWARD TEXAS...AND IN HOW STRONG THE UPPER-LEVEL TROUGH CURRENTLY OVER THE CENTRAL GULF WILL BE OVER THE WESTERN GULF IN A FEW DAYS.

THESE VARYING SOLUTIONS LEAD TO DIFFERENT TRACKS FOR GUSTAV OVER THE NORTHERN GULF. MODELS WITH THE RIDGE EXTENSION AND A STRONGER UPPER-LEVEL TROUGH WEST OF GUSTAV...SUCH AS THE NOGAPS AND UKMET...FORECAST GUSTAV TO TURN WESTWARD TOWARD TEXAS. OTHERS INCLUDING THE GFS...GFDL...AND HWRF...DO NOT SHOW THE RIDGE EXTENSION NOR A STRONG UPPER-LEVEL TROUGH...AND FORECAST GUSTAV TO BE PULLED INTO THE NORTHERN GULF COAST FARTHER EAST.

THE NEW OFFICIAL FORECAST LEANS TOWARD THE LATTER SOLUTIONS AND IS EAST OF THE CONSENSUS...AND REPRESENTS NO SIGNIFICANT CHANGE TO THE PREVIOUS ADVISORY. DUE TO THE NOTABLE MODEL SPREAD LATE IN THE FORECAST PERIOD...IT IS ONCE AGAIN IMPORTANT TO RESTATE THAT IT IS SIMPLY NOT YET POSSIBLE TO DETERMINE EXACTLY WHERE AND WHEN GUSTAV WILL MAKE FINAL LANDFALL.

(For more information on Gustav's track, Alabama reactions and preparation advice and advisories, go to http://al.com/hurricane.)